Pivot bearing unit comprising a braking device

ABSTRACT

A pivot bearing unit ( 18 ), having a pneumatic braking device ( 21 ) with a first and second bearing part ( 22, 23 ), which are embodied as rotatable relative to one another, wherein the braking device ( 21 ) is activatable by means of compressed air ( 36 ) via a compressed air supply line ( 10 ). The braking device ( 21 ) is provided with a brake hose ( 1 ), embedded in a bearing plate ( 14 ), in the first bearing part ( 22 ), and the brake hose ( 1 ) expands as a result of subjection to compressed air ( 36 ) with a motion ( 8 ) in the direction of a free end ( 16 ) and, via an axially movable switching ring ( 2 ), exerts a force ( 17 ) on at least one brake block ( 6 ) of the second bearing part ( 23 ), for transmitting a braking moment ( 15 ) between the first and second bearing parts ( 22, 23 ).

The invention relates to a pivot bearing unit as generically defined by the preamble to claim 1.

Axial pivot bearing units with a braking device for a tripod serve the purpose for instance of horizontal pivoting motion of ceiling supply units in medical units in medical technology that are known for instance from German Patent DE 43 06 805 C1. The medical ceiling supply unit is used for moving medical equipment both horizontally and vertically in a room.

The object of the invention is to create a pivot bearing unit of this generic type which has a simple construction and a reliable mode of operation. Moreover, parts subject to wear (brake blocks and brake hose) are to be easy to replace without dismantling supply lines.

This object is attained by the characteristics of the body of claim 1.

The invention will be described in further detail in terms of an exemplary embodiment.

Shown are:

FIG. 1, in an axial sectional view, a pivot bearing unit in a section taken along the line I-I of FIG. 2;

FIG. 2, in a sectional view, the pivot bearing unit in a section taken along the line II-II of FIG. 1;

FIG. 3, a detail marked III in FIG. 1, showing more detail of a braking device in an inactive state;

FIG. 4, in a side view, the pivot bearing unit of FIG. 1;

FIG. 5, the detail III of FIG. 3, but with the braking device in the activated state; and

FIG. 6, in a side view, one example of an application, with a ceiling-mounted tripod.

FIG. 1 shows a pivot bearing unit 18 with a first and second bearing part 22, 23, which are embodied as a rotatable relative to one another. For braking or fixing a rotary angle, once set, of the two bearing parts 22, 23 relative to one another, the pivot bearing unit 18 is provided with a pneumatic braking device 21, which can be activated by means of compressed air 36 via a compressed air supply line 10. In the first bearing part 22, the braking device 21 is provided with a brake hose 1, embedded in a bearing plate 14, and upon subjection to compressed air 36 the brake hose 1 expands, with a motion 8 in the direction of a free end 16 (FIG. 5) and, via an axially movable switching ring 2, exerts a force 17 on at least one brake block 6 of the second bearing part 23, for transmitting a braking moment 15 between the first and second bearing parts 22, 23. The brake block 6 is screwed firmly to the bearing pot 13. The switching ring 2, once compressed air 36 has been directed into the brake hose 1, presses on the brake lining 4, which is glued to the brake block 6 that is made of aluminum. The brake lining 4 comprises a plastic, for instance of the kind that can be procured from the company known as Jurid.

As the brake hose 1, a rubber hose cut to the proper length is contemplated; a first end is sealed off by means of a stopper, and a second end is provided with a glued-in connection valve (not shown) for the compressed air supply line 10. This brake hose 1 is placed like a ring in the bearing plate 14. The compressed air supply line 10 is passed through the bearing plate 14 for mounting on the ceiling. Because the brake hose 1 has a rectangular outer shape, on the one hand a good seat in the bearing plate 14, which is complementary to it, and on the other a more two-dimensional transmission of force to the switching ring 2 are provided for.

The bearing pot 13 is used for mounting or securing a tripod arm 31, 32, which is to be pivoted, or a tripod column 33. For ducting lines (compressed air supply lines 10, electrical lines 35), the first bearing part 22 has a central opening 37, and the second bearing part 23 is designed as a bearing pot 13. The mounting is done by means of conventional screw fasteners. The flow of force is from the annular securing device 12 via the oblique needle bearing 3 to the bearing pot 13. To assure that the tripod arms 31, 32 cannot move horizontally without being controlled, one braking device 21 each is built in. Later mounting or removal of components of the braking device 21 is possible at any time without removal of a piece of medical equipment 34 (FIG. 6). Thus the otherwise usual removal of gas lines 9 or compressed air supply lines 10 and electrical supply lines 35 becomes unnecessary.

By means of a plastic compressed air supply line 10, compressed air 36 is introduced into the brake hose 1. This is done after actuation of a pneumatic valve (not shown), for instance with a manual actuation in which the brake hose 1 is pumped up and expands in the process. In this process, the brake hose 1 moves the switching ring 2 downward by means of a linear motion 8. Because of a positive-engagement connection with the bearing plate 14, a radial motion 11 of the switching ring 2 during the linear motion 8 is impossible.

The linear motion 8 of the switching ring 2 is limited by the brake blocks 6. The switching ring 2 is seated on the brake linings 4 and generates a braking moment 15. The setting and adjustment of the braking moment 15 are effected by means of threaded pins 7, by which the brake block 6 is raised by a linear motion 8 and fixed with a screw connection 5. By providing a number of brake blocks 6 greater than three, influence can also be exerted on the braking moment 15.

The brake hose 1, 10 is vented by blowing out the compressed air 36, by actuation of a pneumatic valve (not shown). This state is shown in FIGS. 1 and 3. The switching ring 2 moves linearly upward. The pressure on the brake blocks 6 is rescinded, and the braking device 21 is thus ventilated and deactivated.

Permanent braking by means of friction is possible without structural conversion. This becomes important if the compressed air supply is not structurally provided for. For that purpose, the brake blocks 6 are raised by means of threaded pins 7 and fixed by a screw connection 5. Now the switching ring 2 has permanent contact with the brake lining 4 of the brake block 6, as a result of which a frictional braking moment 15 is generated. By means of this construction, wear of the brake hose 1 from friction is avoided.

Wearing parts such as the brake hose 1 and brake blocks 6 can advantageously be replaced without removing the supply lines (electrical and gas supply).

FIG. 2, in a sectional view, shows the pivot bearing unit 18 taken along the line II-II of FIG. 1.

FIG. 3 shows a detail III of FIG. 1, showing the braking device 21 in further detail in an inactive state. The brake hose 1 is embedded on three sides and can thus expand solely in the direction of the free end 16 (FIG. 5). As a consequence, a first spacing D increases to a second spacing D1, and a force 17 is thus exerted on the switching ring 2. The brake hose 1 in this process acts like a pneumatic short-stroke cylinder.

FIG. 4 is a side view of the pivot bearing unit 18 of FIG. 1.

FIG. 5 shows the detail III of FIG. 3, but with the braking device 21 in the activated state as a result of the brake hose 1 that has expanded by means of the compressed air 36.

In FIG. 6, the pivot bearing unit 18 is provided for a tripod 19, in particular a ceiling-mounted tripod 19; a flange plate 20 is provided as the securing device 12 for a ceiling fastening. The ceiling-mounted tripod 19 has a first and second tripod arm 31, 32, each with a further pivot bearing unit 18.1 and 18.2, respectively, which are partly accommodated inside the tripod arms 31, 32. Through a compressed air supply line 10 shown in dashed lines, compressed air 36 (5 bar) is introduced by distribution into the respective brake hose 1, or separate compressed air supply lines 10 are provided for each of the three brake hoses 1 of the pivot bearing units 18, 18.1, 18.2.

LIST OF REFERENCE NUMERALS

-   1 Brake hose -   2 Switching ring -   3 Oblique needle bearing -   4 Brake lining -   5 Screw connection -   6 Brake block -   7 Threaded pin -   8 Linear motion -   9 Plastic hose -   10 Compressed air supply line -   11 Radial motion -   12 Securing device -   13 Bearing pot -   14 Bearing plate -   15 Braking moment -   16 Free end -   17 Force -   18 Pivot bearing unit -   19 Ceiling-mounted tripod -   20 Flange plate -   21 Braking device -   22 First bearing part -   23 Second bearing part -   31 First tripod arm -   32 Second tripod arm -   33 Tripod column -   34 Equipment -   35 Electrical line -   36 Compressed air -   37 Central opening -   D First spacing -   D1 Second spacing 

1. A pivot bearing unit (18), having a pneumatic braking device (21) with a first and second bearing part (22, 23), which are embodied as rotatable relative to one another, wherein the braking device (21) is activatable by means of compressed air (36) via a compressed air supply line (10), characterized in that the braking device (21) is provided with a brake hose (1), embedded in a bearing plate (14), in the first bearing part (22), and the brake hose (1) expands as a result of subjection to compressed air (36) with a motion (8) in the direction of a free end (16) and, via an axially movable switching ring (2), exerts a force (17) on at least one brake block (6) of the second bearing part (23), for transmitting a braking moment (15) between the first and second bearing parts (22, 23).
 2. The pivot bearing unit of claim 1, characterized in that the brake hose (1) has a rectangular shape.
 3. The pivot bearing unit of claim 1, characterized in that the brake block (6) is provided with a brake lining (4).
 4. The pivot bearing unit of claim 1, characterized in that the first bearing part (22) has a central opening (37), and that the second bearing part (23) is designed is as a bearing pot (13).
 5. The pivot bearing unit of claim 1, characterized in that the pivot bearing unit (18) is provided for a tripod (19), in particular for a ceiling-mounted tripod (19), and a securing device (12) with a flange plate (20) is provided. 